Well you can save and load any Drum Maps you like in Cubase too. It doesn’t have a pre-defined location for where to store those files - your choice where to put them. It remembers the last location used - so if you have a bunch of maps in that folder they will be available to load into any Project as needed. If like the OP you don’t want to load them from a file then you can include the maps in a template and whenever you create a Project from that Template all those maps will already be loaded - and of course you can load more from files as the Project progresses. You don’t need to use the loaded maps, they just need to be loaded in the Template to be available for immediate use.
BTW for BFD3 you don’t need to save or load a map into Cubase. Unlike most 3rd party drum VSTi’s (at least last I knew), BFD3 is compliant with the feature to Create Drum Map From Instrument. It will take the currently used internal BFD3 drum map and map that into a Cubase Drum Map.